TM-5835-243-34/EE641-AA-MMl-010/E154
MTT/TO
31S3-4-110-1
assemblies (A8A5, A8A3) from tape deck assembly
NOTE
Same size shims must be used on both
(4) Remove three cable clamps from tape deck
sides of head assembly.
assembly. Cut lacing holding low tape sensor
(5) Calculate required shim size by subtracting
(A8A2) wires to lower anchor bar.
0.003 inch from measured clearance for each of the
(5) Disconnect chassis cable connectors from
guide posts.
tape deck main plate. Tag and unsolder harness
(6) Select any combination of shims which add
assembly wiring from tape deck main plate.
up to calculated shim size.
(6) Remove interlock switch block assembly
(7) Remove head alignment fixture from tape
(A8S1, A8S2) by removing one screw.
transport assembly.
(7) Remove two screws (12) and lock nuts (11)
NOTE
that secure tape deck rear shock mount to chassis
Do not attempt to insert shims with head
(l). Remove two screws that secure tape deck to two
alignment fixture inserted in tape trans-
shock mounts on side of chassis. Do not remove
port.
shock mounts from chassis.
(8) Remove six socket-head screws (2) securing
(8) Loosen two head mounting screws (15) and
front panel assembly (3) to chassis and swing panel
insert required shims between tape deck main plate
out of way.
and head assembly base plate (fig. 3-10). Re-tighten
(9) Slide tape deck assembly (14) forward and
head mounting screws.
out through front of chassis.
(9) Insert head alignment fixture into tape
b. Replacement.
transport and re-measure clearance. Ensure that
(1) Slide tape deck assembly (14) through front
fixture is inserted correctly (fig. 3-10) and that
of chassis and secure rear shock mount to chassis
cartridge locking lever is in locked position.
with two screws (12) and locknuts (11).
(10) Repeat steps (5) to (8) as required until
(2) Secure tape deck to remaining two shock
measured clearance is 0.003 inch to 0.004 inch with
mounts on side of chassis with one screw in each
no more than 0.001 inch variation between posts.
mount.
NOTE
(3) Install front panel (3) on chassis and secure
Ensure that shims remain in proper
it with six screws (2).
position.
(4) Secure interlock switch assembly (A8S1,
(11) Remove one of head mounting screws and
A8S2) with one screw.
apply a drop of sealant to threads. Install and
(5) Solder tagged harness assembly wiring in
tighten screw. -Repeat for remaining screw.
place. Secure chassis cable connectors.
(12) Insert head alignment fixture into tape
(6) Secure harness assembly to tape deck by
transport. Make certain that fixture is inserted
means of three cable clamps. Refer to figure FO-10
completely and that cartridge locking level is in
for harness routing and clamp location.
locked position. Check clearance with head stack
(7) Secure three sensor assemblies (A8A1,
gage. Verify that clearance at both tape guide posts
A8A2, A8A4) and two LED assemblies (A8A3,
is between 0.003 and 0.004 inch with no more than
A8A5) to tape deck. Refer to figure FO-10 for
0.001 inch variation between posts.
location. Retie low tape sensor (A8A2) wires to
(13) Replace two cable clamps holding head
lower anchor bar.
assembly cables to tape deck.
(8) Replace capstan motor assembly B1 (para
(14) Replace power amplifier assembly A9 (para
(9) Replace magentic head assembly PU1 (para
(15) Replace circuit cards A1 through A5 (para
3-33. Harness and Interface Board Assembly
3-32. Tape Deck Assembly A8
(33, fig. 3-7)
(14, fig. 3-7)
a. Removal.
a. Removal.
(1) Remove circuit card assemblies Al through
(1) Remove magnetic head assembly PU1 (para
A5 (para 3-24).
(2) Remove power amplifier assembly A9 (para
(2) Remove capstan motor assembly B1 (para
(3) Remove capstan motor assembly B1 (para
(3) Remove three phototransistor sensor
assemblies (A8A1, A8A2, A8A4) and two LED
3-24
